A Dynamic Wideband Multi-Component Phasor Estimator Using Matrix Theory

Abstract

The spread of renewable energy generation and power electronics-based devices introduces rich harmonic and interharmonic components into power system signals and significantly broadens the frequency band. These multiple components, especially the interharmonic tones, can deteriorate power quality, cause oscillations, trip thermal power generations, and threaten system stability. A first step to mitigate these negative influences is to precisely and fast monitor the signal characteristics, e.g., frequency, amplitude, and phase. This paper proposes a simple and robust index to estimate the number of signal components based on the singular values of the Hankel matrix composed of signal samples. The simplified matrix pencil theory is used to solve signal frequency and the least-squares algorithm is modified to estimate the wideband multi-component phasors. Finally, a set of numerical tests, including the maximum signal component number test, the minimum signal frequency interval test, the dynamic modulation on amplitude and phase, are carried out. Test results verify that the proposed algorithm can realize good wideband multi-component phasor estimations.